STTS751

Addr/Therm output

Doc ID 16483 Rev 5

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Addr/Therm output

The Addr/Therm pin functions normally as an output to alert the system of an over

temperature condition. It is open drain and requires a pull-up resistor. During power-up, the

pull-up value is sensed by the STTS751 to determine what its slave address will be as

depicted in Table 1.

The Therm output is asserted low whenever the temperature exceeds the Therm limit

(address 20h). Only the upper 8 bits of the temperature register are used in the

comparison with the Therm limit. Once asserted, Therm will remain asserted until

temperature falls below the Therm limit minus the therm hysteresis value. For example, if

the Therm limit is 25 °C, and the therm hysteresis value is 10 °C, the Therm output will

assert when the temperature exceeds 25 °C. It will remain asserted until the temperature

falls down to or below 15 °C (25 – 10).

This pin can be used to control a fan or other failsafe device as shown in Figure 4 on page 8.

Figure 7 below shows how the Therm output functions.

Figure 7.

Therm output

AM03033v1

Time

Addr/Therm

Therm limit

Therm Limit minus

Therm Hysteresis

Temperature

Therm

Hysteresis